CN102753804B - Device for estimating changes in target objects - Google Patents

Abstract

The present invention provides an object change estimating device suitable for estimating the change of the object on the time axis. The first estimating unit estimates a change in the object with a delay from an actual change in the object, and the second estimating unit estimates the change in the object before the object actually changes. And, when the object changes, the correction unit corrects one of the first estimation unit and the second estimation unit based on the other unit of the first estimation unit and the second estimation unit, thereby obtaining change of object. Accordingly, it is possible to improve the estimation accuracy for changes in the object.

Description

Object change estimation device

technical field

The present invention relates to the technical field of estimating changes in objects on a time axis.

Background technique

Conventionally, techniques for estimating changes in objects such as engine torque have been proposed. For example, Patent Document 1 proposes a method of estimating a driving force (engine torque) using a disturbance observer. Specifically, this technique proposes a hybrid system that transmits power to tires via a transmission having a function of switching between a first mode and a second mode with different properties through connection and separation of friction elements. In a power vehicle, the driving force is estimated by a disturbance observer in the first mode or in the second mode, and the motor torque is controlled by feedforward acceleration control in the mode transition transition period.

In addition, Patent Document 2 proposes a method of estimating engine torque with reference to the intake air amount of the engine.

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-34076

Patent Document 2: Japanese Patent Laid-Open No. 2002-201998

Contents of the invention

However, in the technique described in the above-mentioned Patent Document 1, the engine torque may not be estimated with high accuracy during a mode transition transition period or the like. This is because, for example, in an estimation method based on a disturbance observer, since differentiation is performed during calculation, it is practical to use a filter that removes noise accompanying this process, and therefore the calculation of the actual engine torque Vary with a delayed value.

On the other hand, in the technology described in Patent Document 2, for example, due to the influence of friction (friction) changes and/or fuel state changes depending on the temperature of the engine and/or cooling water, it may not be possible to estimate the engine torque with high accuracy. .

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide an object change estimating device capable of estimating a change in an object such as engine torque with high accuracy.

In one aspect of the present invention, the object change estimating device is a device for estimating the change of the object on the time axis, and includes: a first estimating unit for estimating with a delay from the actual change of the object a change of the object; a second estimating unit for estimating the change of the object before the object actually changes; and a correction unit for the One of the first estimating unit and the second estimating unit performs correction based on the other of the first estimating unit and the second estimating unit, thereby obtaining a change in the object.

The object change estimating device described above is suitable for estimating the change of the object on the time axis. The first estimation unit estimates a change in the object with a delay from an actual change in the object. For example, the first estimation unit detects or acquires a value related to an actual change of the object, and obtains the change of the object based on such a value. In addition, the second estimating unit estimates the change of the object before the object actually changes. In addition, when the object changes, the correction unit corrects one of the first estimation unit and the second estimation unit based on the other unit of the first estimation unit and the second estimation unit, thereby obtaining change of object. Accordingly, it is possible to improve the estimation accuracy for changes in the object. "Estimation" of the first estimation unit is a concept that can also include "acquisition" and "detection" of changes in objects.

In one aspect of the object change estimating device described above, the correction unit may use the second estimating unit to calculate the change of the object estimated by the first estimating unit relative to the actual change of the object. The correction is performed by adding or subtracting the calculated change amount to the change amount of the object estimated by the first estimating means within a delay time of the object. .

In addition, the correcting unit may perform the correction when the change in the object estimated by the first estimating unit is greater than a predetermined value.

In another aspect of the object change estimating device described above, the correcting means may change the predetermined value based on the gradient of the change of the object estimated by the second estimating means. Thereby, the estimation accuracy with respect to the change of an object can be further improved.

In another aspect of the object change estimating device described above, the first estimating unit may change the gradient of the object change estimated by the second estimating unit for estimating the The first estimating means estimates a control value adjusted with respect to a delay time of an actual change of the object such that the delay time changes. Thereby, the estimation accuracy with respect to the change of an object can be further improved.

In another aspect of the object change estimating device described above, the first estimating unit may set a lower limit to be used for the control value when changing the control value for adjusting the delay time. The warning value, the object change estimation apparatus further includes a control unit that performs control to limit the change of the object such that the control value complies with the lower limit warning value. Thereby, it is possible to appropriately limit the change of the object that cannot guarantee the estimation accuracy.

In another aspect of the object change estimating device described above, the correcting unit may learn a delay time of the estimation performed by the first estimating unit with respect to the estimation performed by the second estimating unit, The correction is made based on the learned delay time. Thereby, it is possible to estimate the initial behavior and the like in the change of the object with high precision.

Preferably, the correcting unit may perform the correction based on the learned delay time when the change in the object estimated by the first estimating unit is equal to or less than a predetermined value.

In another aspect of the object change estimating device described above, the correcting unit may correct all the values estimated by the second estimating unit based on a change in a state value related to a change in the object. The change of the object is corrected by the first estimating unit based on the corrected change of the object. Accordingly, it is possible to effectively improve the estimation accuracy of changes in the object.

In the object change estimating device described above, preferably, the first estimating unit estimates a change in engine torque as a change in the object based on a disturbance observer, and the second estimating unit estimates a change in engine torque based on a disturbance observer. The change in the engine torque is estimated as the change in the object.

In the object change estimating device described above, it is preferable that the object change estimating device is adapted to perform a speed change between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements from each other. In the hybrid vehicle in which the mode is switched, the correction means performs the correction when the shift mode is switched. Thereby, the shift quality of the hybrid vehicle can be improved, and the responsiveness of the charge and discharge control of the battery can be improved.

In addition, it is preferable that the correction unit continues to perform the correction until the joining of the joining elements is completed. Thereby, the engageability of the engaging element can be improved, and it is possible to effectively suppress a delay in shifting time, a shifting shock, and the like.

The object change estimating device of the present invention is suitable for estimating the change of the object on the time axis. The first estimating unit estimates a change in the object with a delay from an actual change in the object, and the second estimating unit estimates the change in the object before the object actually changes. In addition, when the object changes, the correction unit corrects one of the first estimation unit and the second estimation unit based on the other unit of the first estimation unit and the second estimation unit, thereby obtaining change of object. Accordingly, it is possible to improve the estimation accuracy for changes in the object.

Description of drawings

FIG. 1 shows a schematic configuration of a hybrid vehicle according to an embodiment.

Fig. 2 shows the structures of the motor generator and the power transmission mechanism.

Fig. 3 shows a nomographic diagram of the power distribution mechanism in a fixed gear ratio mode.

FIG. 4 shows an example of the relationship between shift control and shift shock in a hybrid vehicle.

FIG. 5 shows an example of engine torque estimated by the first estimation method and the second estimation method.

FIG. 6 is a diagram illustrating a method of estimating engine torque in the first embodiment.

7 is a flowchart showing engine torque estimation processing in the first embodiment.

FIG. 8 is a diagram for explaining problems when the second predetermined value is relatively small and the filter time constant of the disturbance observer is large.

FIG. 9 is a diagram for explaining a method of determining a second predetermined value and a filter time constant of a disturbance observer in the second embodiment.

FIG. 10 is a diagram for explaining the effect of the engine torque estimation method in the second embodiment.

FIG. 11 is a diagram for explaining problems when the torque fluctuation is large and the torque change gradient is large.

FIG. 12 is a diagram for concretely explaining a method of limiting the engine torque variation gradient in the third embodiment.

FIG. 13 is a diagram for explaining the effect of the engine torque estimation method of the third embodiment.

FIG. 14 is a diagram for explaining problems that occur when the correction of the detected torque is not continued until the engagement of the jaws is completed.

FIG. 15 is a diagram for explaining the effects of the engine torque estimation method of the fourth embodiment.

16 is a flowchart showing engine torque estimation processing in the fourth embodiment.

FIG. 17 is a diagram for concretely explaining a method of estimating engine torque in the fifth embodiment.

18 is a flowchart showing engine torque estimation processing in the fifth embodiment.

FIG. 19 is a diagram for explaining problems that occur when predicted torque deviates from actual torque (and detected torque).

FIG. 20 is a diagram for concretely explaining a method of estimating engine torque according to the sixth embodiment.

21 is a flowchart showing engine torque estimation processing in the sixth embodiment.

Label description

1 engine

3 output shaft

4ECU

7 jaw brake part

20 power distribution mechanism

31 Converter

32, 34 converter

33HV battery

40 stroke sensor (stroke sensor)

41 rotation sensor

MG1 first motor generator

MG2 second motor generator

Detailed ways

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[device structure]

FIG. 1 shows a schematic configuration of a hybrid vehicle to which the present invention is applied. The example shown in FIG. 1 is a so-called mechanical split 2-motor type hybrid vehicle, and includes an engine 1 , a first motor generator MG1 , a second motor generator MG2 , and a power split mechanism 20 . An engine 1 corresponding to a power source, and a first motor generator MG1 corresponding to a rotational speed control unit are connected to a power split unit 20 . The output shaft 3 of the power distribution mechanism 20 is connected to the second motor generator MG2 as an auxiliary power source for assisting the driving torque or assisting the braking force. The second motor generator MG2 is connected to the output shaft 3 via the MG2 transmission unit 6 . Furthermore, the output shaft 3 is connected to left and right drive wheels 9 via a final reduction gear 8 . The first motor generator MG1 and the second motor generator MG2 are electrically connected via a battery, an inverter, or an appropriate controller (refer to FIG. 2 ), or are directly connected electrically, and are configured to utilize the power generated by the first motor generator MG2. of electric power to drive the second motor generator MG2.

The engine 1 is a heat engine that burns fuel to generate power, and examples thereof include a gasoline engine, a diesel engine, and the like. The first motor generator MG1 receives torque from the engine 1 and rotates to mainly generate electricity. The first motor generator MG1 acts as a reaction force of the torque accompanying the electricity generation. The rotational speed of engine 1 is continuously varied by controlling the rotational speed of first motor generator MG1. Such a speed change mode is called a continuously variable speed change mode. The continuously variable transmission mode is realized by the differential operation of the power distribution mechanism 20 described later.

The second motor generator MG2 is a device that assists (assists) the driving torque or the braking force. In the case of assisting drive torque, the second motor generator MG2 is supplied with electric power and functions as an electric motor. On the other hand, in the case of assisting the braking force, the second motor generator MG2 functions as a generator that rotates the driving wheels 9 by torque transmitted from them to generate electric power.

FIG. 2 shows the configurations of the first motor generator MG1, the second motor generator MG2, and the power split mechanism 20 shown in FIG. 1 .

The power split mechanism 20 is a mechanism that distributes the output torque of the engine 1 to the first motor generator MG1 and the output shaft 3, and is configured to generate a differential action. More specifically, it is equipped with a plurality of sets of differential mechanisms. Among the four rotating elements that generate a differential action with each other, the engine 1 is connected to the first rotating element, the first motor generator MG1 is connected to the second rotating element, and the output shaft 3 is connected to the second rotating element. The third rotary element is linked. The fourth rotary element can be fixed by means of the dog catch 7 .

The dog braking unit 7 is configured as an engaging mechanism including an engaging element (not shown) provided with a plurality of cogs and an engaged element (not shown), and is controlled by the brake operating unit 5 . For example, the engagement element is configured to be stroked and rotated. Instead of the dog stopper 7 , a clutch (dog clutch) configured to engage rotating engagement elements may be used. Hereinafter, the jaw brake portion 7 or the jaw clutch is simply referred to as a “dog portion”.

The continuously variable speed change mode is realized by continuously changing the rotation speed of the engine 1 by continuously changing the rotation speed of the first motor generator MG1 in a state where the dog brake portion 7 is not fixing the fourth rotation element. On the other hand, in the state where the dog 7 fixes the fourth rotation element, the gear ratio determined by the power distribution mechanism 20 is fixed in an overdrive state (ie, a state in which the engine speed is smaller than the output speed) , to achieve a fixed gear ratio mode.

In the present embodiment, as shown in FIG. 2 , the power distribution mechanism 20 is configured by combining two planetary gear mechanisms. The first planetary gear mechanism includes a ring gear 21 , a carrier 22 , and a sun gear 23 . The second planetary gear mechanism is a double pinion type, and includes a ring gear 25 , a carrier 26 , and a sun gear 27 .

The output shaft 2 of the engine 1 is connected to the carrier 22 of the first planetary gear mechanism, and the carrier 22 is connected to the ring gear 25 of the second planetary gear mechanism. These constitute the first rotating element. The rotor 11 of the first motor generator MG1 is connected to the sun gear 23 of the first planetary gear mechanism, and these constitute the second rotating element.

The ring gear 21 of the first planetary gear mechanism and the carrier 26 of the second planetary gear mechanism are connected to each other and connected to the output shaft 3 . These constitute the third rotating element. In addition, the sun gear 27 of the second planetary gear mechanism is connected to the rotating shaft 29 and constitutes a fourth rotating element together with the rotating shaft 29 . The rotating shaft 29 can be fixed by the dog stopper 7 .

The power supply unit 30 includes an inverter 31 , a converter 32 , an HV battery 33 , and an inverter 34 . First motor generator MG1 is connected to inverter 31 through a power line 37 , and second motor generator MG2 is connected to inverter 31 through a power line 38 . In addition, inverter 31 is connected to converter 32 , and converter 32 is connected to HV battery 33 . Furthermore, HV battery 33 is connected to auxiliary battery 35 via converter 34 .

Inverter 31 transmits and receives electric power between motor generators MG1 and MG2. During regeneration of the motor generators, inverter 31 converts electric power generated by motor generators MG1 and MG2 through regeneration into direct current, and supplies the electric power to converter 32 . Converter 32 converts the voltage of the electric power supplied from inverter 31 to charge HV battery 33 . On the other hand, during power running of the motor generator, DC power output from HV battery 33 is boosted by converter 32 and supplied to motor generator MG1 or MG2 via power supply line 37 or 38 .

The electric power of the HV battery 33 is converted into voltage by the converter 34 and supplied to the auxiliary machine battery 35, and is used for driving various auxiliary machines.

Operations of inverter 31 , converter 32 , HV battery 33 , and converter 34 are controlled by ECU 4 . The ECU 4 controls the operation of each element in the power supply unit 30 by sending a control signal S4. In addition, necessary signals indicating the state of each element in the power supply unit 30 are supplied to the ECU 4 as a control signal S4 . Specifically, SOC (State Of Charge) indicating the state of the HV battery 33, input and output control values of the battery, and the like are supplied to the ECU 4 as a control signal S4.

ECU 4 controls these devices by transmitting and receiving control signals S1 to S3 between engine 1 , first motor generator MG1 , and second motor generator MG2 . In addition, the ECU 4 supplies a brake operation instruction signal S5 to the brake operation unit 5 . The brake operation unit 5 controls engagement (fixation) and disengagement of the dog brake unit 7 based on the brake operation instruction signal S5. As will be described in detail later, the ECU 4 functions as a change estimating device of the object of the present invention, and estimates the engine torque.

FIG. 3 shows a nomographic diagram of the power split mechanism 20 in the fixed gear ratio mode. In the fixed gear ratio mode, as shown by black circles in FIG. 3 , the cogs of the engaging element mesh with the cogs of the engaged element, thereby fixing the dog stopper 7 . In the continuously variable transmission mode, as indicated by an arrow 90 , the reaction force of the engine torque is supported by the first motor generator MG1 . FIG. 3 shows a nomographic diagram in the fixed speed ratio mode, but for convenience of explanation, the continuously variable speed mode will be described using this diagram. In contrast, in the fixed gear ratio mode, as indicated by arrow 91 , the reaction force of the engine torque is supported mechanically in the dog part 7 .

[How to estimate engine torque]

Next, the method of estimating the engine torque performed by the ECU 4 in the present embodiment will be described. In the present embodiment, the ECU 4 estimates the engine torque so that highly accurate engine torque can be obtained.

The reason for this is as follows. In a hybrid vehicle, when a shift is performed using the first motor generator MG1 , the user may feel a delay or a shock of the shift (hereinafter referred to as "shift shock"). In addition, in a hybrid vehicle, in a transient state where the engine speed or engine torque changes, the accuracy of the charge and discharge control of the battery decreases, and the use of the battery becomes stricter, and the potential (voltage) of the battery may not be drawn out. . Such a problem is considered to be caused by deterioration in the estimation accuracy of the engine torque change at the time of transition.

FIG. 4 is a conceptual diagram showing an example of the relationship between shift control and shift shock in a hybrid vehicle. In FIG. 4 , time is shown on the horizontal axis, and torque is shown on the vertical axis. Specifically, the curves A1 and A2 represent the amount of engine torque provided in the output shaft torque, and the curve A1 represents the engine torque estimated based on the intake air amount of the engine (estimated by the second estimation method described later). engine torque), and the curve A2 represents the actual engine torque. Furthermore, curve A3 represents the supply amount of the torque of the first motor generator MG1 in the output shaft torque. This torque is adjusted based on the torque shown in curve A1. It was found that in this case, as indicated by the shaded area A4, a prediction error occurs with respect to the engine torque. As a result, as indicated by the hatched area A5, a step difference (step difference) occurs in the output shaft torque, that is, a shift shock occurs. From this, it can be said that the estimation accuracy of the engine torque affects the shift quality.

As described above, in the present embodiment, the ECU 4 estimates the engine torque so that highly accurate engine torque can be obtained. Specifically, the ECU 4 uses a method of estimating engine torque based on a disturbance observer (hereinafter referred to as “first estimating method”) and an estimating method of engine torque based on the amount of intake air of the engine (hereinafter referred to as “first estimating method”). The second estimation method") is to estimate the engine torque. The first estimation method corresponds to a method of estimating a disturbance torque value for the rotational speed control of the first motor generator MG1. That is, the first estimation method corresponds to a method of estimating the past engine torque based on the amount of change in the rotational speed of the first motor generator MG1 connected to the engine 1 . In addition, the second estimation method corresponds to a method of estimating the engine torque by predicting the engine intake air charge amount. "Estimation" in the first estimation method is a concept that may include "acquisition" and "detection" of engine torque.

Here, in the first estimation method, since the engine torque is estimated using the rotational speed information of the first motor generator MG1, a value with relatively high accuracy can be obtained. That is, the estimation of the engine torque by the first estimation method can be said to correspond to the detection of the engine torque using the sensor. However, in the first estimation method, since differentiation is performed during the calculation, it is practically necessary to use a filter (differential noise removal filter) that removes noise accompanying the differentiation, so that the actual engine torque relative to the actual engine torque can be obtained. Changes have a delayed value.

On the other hand, the second estimation method can estimate the engine torque to be output in the future based on the engine power command value and/or the engine rotation speed command value and the like. That is, with the second estimation method, it can be said that the future engine torque is predicted. However, the second estimating method may not be able to estimate the engine torque with high accuracy because, for example, it is affected by changes in friction depending on the temperature of the engine and/or cooling water and/or changes in the combustion state.

FIG. 5 shows an example of engine torque estimated by the first estimation method and the second estimation method. In FIG. 5 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, the curve B1 represents the engine torque estimated by the first estimation method, the curve B2 represents the engine torque estimated by the second estimation method, and the curve B3 represents the actual engine torque. From this, it can be seen that the engine torque estimated by the first estimation method is delayed with respect to the actual engine torque. In FIG. 5 , for convenience of description, the change in engine torque estimated by the second estimation method roughly coincides with the actual change in engine torque. The estimated engine torque change tends to deviate from the actual engine torque change.

Therefore, in the present embodiment, the ECU 4 estimates the engine torque using both the first estimation method and the second estimation method in order to grasp the actual engine torque shown by the curve B3 in FIG. 5 in real time. Specifically, the ECU 4 obtains the current engine torque by correcting the engine torque estimated by the first estimation method with the engine torque estimated by the second estimation method. Thereafter, the ECU 4 performs shift control and the like using the obtained engine torque. In this way, the ECU 4 functions as the first estimating unit, the second estimating unit, and the correcting unit in the present invention.

Hereinafter, specific embodiments (first to sixth embodiments) related to an estimation method of engine torque will be described.

(first embodiment)

In the first embodiment, the ECU 4 uses the second estimation method to calculate the engine torque change amount after the delay time from the actual engine torque change estimated by the first estimation method, and the engine torque estimated by the first estimation method is The engine torque is obtained by adding or subtracting the amount of change in engine torque thus calculated to the torque. Specifically, the ECU 4 detects a change equivalent to a change in the engine torque estimated by the second estimation method by the first estimation method, thereby synchronizing the two pieces of engine torque information estimated by the first estimation method and the second estimation method. . Then, based on the thus synchronized engine torque obtained by the second estimation method, the ECU 4 calculates the engine torque change amount after the delay time of the first estimation method, and adds or The calculated engine torque variation is subtracted. Thereby, the estimation accuracy of the transient engine torque can be improved.

Hereinafter, the engine torque estimated by the first estimation method is appropriately described as "detected torque", the engine torque estimated by the second estimation method is appropriately described as "predicted torque", and the actual engine torque It is appropriately described as "actual torque". In addition, the engine torque change amount added or subtracted to the engine torque (detected torque) estimated by the first estimation method as described above is appropriately described as "corrected torque", and the detected The engine torque obtained by correcting the torque is appropriately described as "calculated value torque".

FIG. 6 is a diagram for concretely explaining a method of estimating engine torque in the first embodiment. In FIG. 6 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te1 shows an example of predicted torque, curve Td1 shows an example of detected torque, curve Tr1 shows an example of actual torque, and curve Tc1 shows an example of calculated torque.

A method of obtaining the calculated torque Tc1 in the first embodiment will be specifically described. The ECU 4 starts processing for correcting the detected torque Td1 when the change in the predicted torque Te1 is greater than a threshold value (hereinafter referred to as "first predetermined value"). Also, the ECU 4 stores the predicted torque Te1 at that time when the change in the predicted torque Te1 is larger than the first predetermined value. In the example shown in FIG. 6, since the change in predicted torque Te1 at time t11 is larger than the first predetermined value, ECU 4 stores predicted torque Te1 at time t11.

Furthermore, the ECU 4 detects a change equivalent to such a change in the predicted torque Te1 based on the detected torque Td1. Hereinafter, such detection is referred to as "rising detection". Specifically, the ECU 4 performs rise detection by determining whether or not a change in the detected torque Td1 is larger than a threshold value (hereinafter referred to as "second predetermined value"). In addition, the ECU 4 stores the detected torque Td1 at that time when the change in the detected torque Td1 is greater than the second predetermined value (that is, when a rise is detected). In the example shown in FIG. 6, since the change in the detected torque Td1 at the time t12 is larger than the second predetermined value, the ECU 4 stores the detected torque Td1 at the time t12.

Next, the ECU 4 synchronizes these two torques based on the predicted torque Te1 and the detected torque Td1 stored as described above at time t12 when the rise is detected in this way. Next, the ECU 4 calculates the engine torque from the time t11 to the elapse of the delay time τ1 from the time t11 based on the predicted torque Te1 thus synchronized using the delay time τ1 from the actual engine torque change estimated by the first estimation method. The amount of change ΔT1. Such engine torque change amount ΔT1 corresponds to the correction torque. The delay time τ1 corresponds to the delay characteristic value of the disturbance observer in the first estimation method. Specifically, the delay time τ1 corresponds to the filter time constant of the disturbance observer. For example, the perturbation observer's filter uses a first-order delay filter.

Next, the ECU 4 corrects the detected torque Td1 by adding the correction torque ΔT1 calculated as described above to the detected torque Td1 as shown by the white arrow in FIG. 6 . Thereby, the calculated value torque Tc1 can be obtained. The ECU 4 performs such correction only when the absolute value of the correction torque ΔT1 is greater than a threshold value (hereinafter referred to as "third predetermined value"). The third predetermined value is set in advance according to the required accuracy.

In FIG. 6 , for convenience of description, a graph in which the value of the predicted torque Te1 and the value of the actual torque Tr1 are approximately coincident is shown (in detail, the value of the predicted torque Te1 and the value of the actual torque Tr1 are shown only when (a graph in which deviation occurs on the time axis), but actually, the value of the predicted torque Te1 tends to deviate from the value of the actual torque Tr1. Specifically, the value of the predicted torque Te1 and the value of the actual torque Tr1 may deviate on the torque axis.

7 is a flowchart showing engine torque estimation processing in the first embodiment. This process is repeatedly executed by the ECU 4 .

First, in step S101, the ECU 4 starts storing the predicted torque estimated by the second estimation method. Next, the process proceeds to step S102. In step S102, the ECU 4 determines whether the predicted torque is greater than a first predetermined value. In a case where the predicted torque is greater than the first predetermined value (YES in step S102), the process proceeds to step S103. In this case, the ECU 4 starts processing for correcting the detected torque. On the other hand, when the predicted torque is equal to or less than the first predetermined value (NO in step S102 ), the process for correcting the detected torque is not started, and the process ends.

In step S103, the ECU 4 determines whether or not the detected torque estimated by the first estimation method is greater than a second predetermined value. By making such a determination, the ECU 4 detects an increase in the detected torque. In a case where the detected torque is greater than the second predetermined value (YES in step S103), the process proceeds to step S104. In this case, it can be said that the detected torque has increased, so the ECU 4 stores the detected torque (step S104). Next, the process proceeds to step S105. On the other hand, when the detected torque is equal to or less than the second predetermined value (NO in step S103 ), since the detected torque cannot be said to have increased, the process returns to step S103 .

In step S105 , the ECU 4 synchronizes the two torques based on the predicted torque stored in step S101 and the detected torque stored in step S104 at the rising detection position. Next, the process proceeds to step S106. In step S106, the ECU 4 calculates a correction torque for correcting the detected torque. Specifically, the ECU 4 calculates the amount of change in engine torque after the delay time based on the estimated torque that has been synchronized using the delay time from the actual engine torque change estimated by the first estimation method, and the engine torque The amount of torque change is used as the correction torque. Next, the process proceeds to step S107.

In step S107, the ECU 4 determines whether or not the absolute value of the correction torque calculated in step S106 is greater than a third predetermined value. When the absolute value of the correction torque is greater than the third predetermined value (YES in step S107), the process proceeds to step S108. In step S108, the ECU 4 corrects the detected torque based on the corrected torque. That is, the ECU 4 adds the correction torque calculated in step S106 to the detected torque stored in step S104 to calculate the calculated value torque. Then, the process returns to step S104. On the other hand, when the absolute value of the correction torque is equal to or less than the third predetermined value ("No" in step S107), the process ends. In this case, correction of the detected torque is not performed.

According to the engine torque estimation method of the first embodiment described above, the accuracy of detecting a transient change in engine torque can be improved. In addition, by performing shift control or the like using the engine torque thus estimated, the shift quality of the hybrid vehicle can be improved, and the responsiveness of the charge and discharge control of the battery can be improved.

In the above, although the method of estimating the engine torque performed when the engine torque is increased has been described, such an estimation method may be similarly performed when the engine torque is decreased. In this case, the detection torque can be corrected by subtracting the correction torque from the detection torque obtained by the first estimation method.

(second embodiment)

Next, the method of estimating the engine torque according to the second embodiment will be described. Also in the second embodiment, basically the same method as the method of estimating the engine torque in the first embodiment is used. However, the second embodiment differs from the first embodiment in that the second predetermined value for detecting an increase in the detected torque is changed based on the change gradient of the predicted torque, and the first estimated value is changed. The filter time constant of the disturbance observer in the method (in other words the filter delay of the disturbance observer). That is, in the second embodiment, the ECU 4 changes the second predetermined value and the filter time constant of the disturbance observer according to the change gradient of the predicted torque so that the threshold value (the second predetermined value ) exceeds the noise-induced variation of the disturbance observer.

Such reasons are as follows. In the engine torque estimation method of the first embodiment as described above, when a filter time constant that makes the delay of the disturbance observer small is selected (that is, when a filter with a relatively small value is selected time constant), there is a tendency for the disturbance caused by noise to become larger. For this reason, it may be difficult to properly synchronize the two pieces of engine torque information, that is, it may be difficult to properly detect an increase in the detected torque. On the other hand, when a filter time constant is selected that reduces the disturbance due to noise (that is, when a filter time constant having a relatively large value is selected), there is a possibility that the delay of the disturbance observer becomes large. tendency. Therefore, the period during which the detection torque can be appropriately corrected tends to be shortened. Therefore, for example, it may not be possible to appropriately respond to short-term torque changes.

Specifically, it will be described with reference to FIG. 8 . FIG. 8 is a diagram for explaining problems when the second predetermined value for detecting an increase in the detected torque is small and the filter time constant of the disturbance observer is large (that is, the filter delay is large). In FIG. 8 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te21 shows an example of predicted torque, curve Td21 shows an example of detected torque, curve Tr21 shows an example of actual torque, and curve Tc21 shows an example of calculated torque. The calculated torque Tc21 is obtained based on the correction torque ΔT21 corresponding to the delay time τ21 by the same method as the method of estimating the engine torque in the first embodiment.

In this case, it was found that since the second predetermined value is small and the filter time constant of the disturbance observer (corresponding to the delay time τ21) is large, as shown by the arrow T21 in FIG. The correction period is shorter. In other words, it is found that the period to start applying the calculated value torque Tc21 is delayed.

As described above, in the second embodiment, in order to overcome such a problem, the ECU 4 changes the second predetermined value and the filter time constant of the disturbance observer based on the change gradient of the predicted torque. Specifically, the ECU 4 changes the second predetermined value and the filter time constant of the disturbance observer so that "(second predetermined value)>(variation due to noise of the disturbance observer)" depends on the change gradient of the predicted torque.

FIG. 9 is a diagram for explaining a method of determining a second predetermined value and a filter time constant of a disturbance observer in the second embodiment. FIG. 9( a ) shows an example of the relationship between the predicted torque change gradient (horizontal axis) and the second predetermined value (vertical axis). According to such relationship, according to the change gradient of the predicted torque, the second predetermined value corresponding thereto is determined. It can be seen that in this case, the second predetermined value having a smaller value is determined as the change gradient of the predicted torque is smaller, and the second predetermined value is determined having a larger value as the change gradient of the predicted torque is larger.

FIG. 9( b ) shows an example of the relationship between the filter time constant (horizontal axis) of the disturbance observer and the noise variation (vertical axis) of the disturbance observer. The noise variation of the disturbance observer, indicated by arrow 97, is determined according to a second predetermined value. Therefore, the second predetermined value is determined based on the change gradient of the predicted torque, and the noise variation corresponding to the second predetermined value is determined. And, based on the specified noise variation, the filter time constant of the disturbance observer corresponding thereto is determined. In this case, a filter time constant having a larger value is determined as the noise variation is smaller, and a filter time constant having a smaller value is determined as the noise variation is larger.

Therefore, a filter time constant having a larger value is determined as the gradient of change of the predicted torque is smaller, and a filter time constant having a smaller value is determined as the gradient of change of the predicted torque is larger. Thereby, small change detection can be appropriately realized when the change gradient of the predicted torque is small, and early detection can be properly realized when the change gradient of the predicted torque is large. The relationship shown in FIG. 9( a ) and FIG. 9( b ) is predetermined so as to satisfy the relationship of "(second predetermined value)>(variation due to noise of the disturbance observer)".

FIG. 10 is a diagram for explaining the effect of the engine torque estimation method of the second embodiment. In FIG. 10 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te22 shows an example of predicted torque, curve Td22 shows an example of detected torque, curve Tr22 shows an example of actual torque, and curve Tc22 shows an example of calculated torque. The calculated torque Tc22 is obtained based on the correction torque ΔT22 corresponding to the delay time τ22 by the same method as the method of estimating the engine torque in the first embodiment.

In this case, by the method described above, the second predetermined value having a relatively large value and the filter time constant having a relatively small value are determined based on the change gradient of the predicted torque. Therefore, it can be seen that as indicated by the arrow T22 in FIG. 10 , the period during which the detection torque Td22 can be properly corrected is long. Specifically, it can be seen that the period during which the detection torque Td22 is corrected is longer than the period during which the detection torque Td21 shown in FIG. 8 is corrected.

According to the engine torque estimation method of the second embodiment described above, the accuracy of detecting a transient change in engine torque can be further improved.

Although the method of estimating the engine torque performed when the engine torque is increased has been described above, such an estimation method can be similarly performed when the engine torque is decreased. That is, it is possible to change the threshold value for detecting a drop in the detected torque based on the change gradient of the predicted torque in the same procedure when the engine torque drops (the same threshold value may be used for the second predetermined value and the absolute value). value), and the filter time constant of the disturbance observer of the first estimation method can be changed.

In addition, although the above shows an example in which both the second predetermined value and the filter time constant of the disturbance observer are changed based on the change gradient of the predicted torque, only the second predetermined value may be changed based on the change gradient of the predicted torque. One of a predetermined value and the filter time constant of the disturbance observer.

(third embodiment)

Next, the method of estimating the engine torque according to the third embodiment will be described. Also in the third embodiment, basically the same method as the method of estimating the engine torque in the first embodiment is used. However, in the third embodiment, the difference from the first embodiment and the second embodiment is that the filter time of the disturbance observer is considered in consideration of the characteristics of the main factor of the noise of the disturbance observer in the first estimation method. The constant sets the lower limit warning value, and controls the engine torque so that the filter time constant complies with the lower limit warning value. That is, in the estimation method of the engine torque of the second embodiment, the ECU 4 prohibits the command of the gradient of the engine torque change requiring the filter time constant lower than the lower limit warning value set in this way (in other words, the engine torque change gradient setting limits).

More specifically, the ECU 4 first sets a lower limit warning value for the filter time constant of the disturbance observer based on the noise characteristic of the operating point, etc., and obtains a change gradient of the engine torque detectable at the set lower limit warning value. In addition, the ECU 4 restricts the command of the engine torque so that the change in the engine torque exceeding the obtained change gradient does not occur.

The reason for this is as follows. When the torque fluctuation is large (that is, when the fluctuation due to noise is large), it can be said that the filter time constant needs to be increased in order to remove the noise. On the other hand, when the gradient of torque change is large (that is, when the gradient of change in predicted torque is large), it can be said that the time constant of the filter needs to be reduced in order to shorten the time for rising detection. Therefore, when the torque fluctuation is large and the torque change gradient is large, it is considered that a condition in which noise removal and rising detection time can not be achieved at the same time arises. Therefore, in the method of the above-mentioned second embodiment, it can be said that when the change gradient of the predicted torque is large or the fluctuation due to the noise of the disturbance observer is large, it may not be possible to appropriately select second predetermined value)>(noise-induced variation of the disturbance observer)" and the second predetermined value and the filter time constant of the disturbance observer.

Specifically, description will be given with reference to FIG. 11 . FIG. 11 is a diagram for explaining problems in the case where the torque fluctuation is large and the torque change gradient is large. In FIG. 11 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te31 shows an example of predicted torque, curve Td31 shows an example of detected torque, and curve Tr31 shows an example of actual torque. In this case, it can be said that since the torque fluctuation is large and the gradient of the torque change is large, a condition in which noise removal and rising detection time cannot be achieved at the same time occurs. Therefore, it is considered that the rise of the detected torque Td31 cannot be appropriately detected due to the large noise in the second predetermined value determined from the change gradient of the predicted torque by the method described in the second embodiment.

Based on the above, in the third embodiment, in order to overcome such a problem, the ECU 4 sets the lower limit warning value for the filter time constant of the disturbance observer, and prohibits engine torque variation that requires a filter time constant lower than the lower limit warning value. Gradient instructions. Basically, the engine torque response limit characteristic and/or the exhaust gas characteristic based on the catalyst composition are considered, and the command of the slowest engine torque change gradient is issued, but in the third embodiment, on this basis, the disturbance observation The structure of the first estimation method of the sensor is regarded as a sensor, and the command of the gradient of the engine torque change is issued in consideration of its accuracy. That is, the instruction of the gradient of the engine torque change for which the accuracy of the sensor cannot be guaranteed is prohibited.

FIG. 12 is a diagram for specifically explaining a method of limiting the engine torque change gradient in the third embodiment. In FIG. 12( a ), the engine speed is shown on the horizontal axis and the engine torque is shown on the vertical axis, showing a graph for determining the lower limit warning value of the filter time constant of the disturbance observer. Specifically, in FIG. 12( a ), the torque fluctuation characteristics at the operating points of the engine are shown by contour lines. Based on such torque fluctuation characteristics, the lower limit warning value of the filter time constant is selected.

FIG. 12( b ) shows an example of the relationship between the filter time constant (horizontal axis) of the disturbance observer and the noise variation (vertical axis) of the disturbance observer. Based on such a relationship, the noise variation corresponding to the lower limit warning value of the filter time constant of the disturbance observer selected as described above is determined.

FIG. 12( c ) shows an example of the relationship between the predicted torque change gradient (horizontal axis) and the second predetermined value (vertical axis). The second predetermined value is determined by the noise variation of the disturbance observer, as indicated by arrow 98 . Therefore, the noise variation is determined according to the lower limit warning value of the filter time constant, and the second predetermined value corresponding to the noise variation is determined. This corresponds to obtaining a threshold value that can appropriately detect an increase in the detected torque. And, the change gradient of the predicted torque corresponding thereto is determined based on the second predetermined value thus determined. In the third embodiment, as shown by the white arrow in FIG. 12( c ), the ECU 4 does not issue a command for an engine torque having a change gradient larger than the change gradient determined in this way.

FIG. 13 is a diagram for explaining the effect of the engine torque estimation method of the third embodiment. In FIG. 13 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te32 shows an example of predicted torque, curve Td32 shows an example of detected torque, curve Tr32 shows an example of actual torque, and curve Tc32 shows an example of calculated torque. The calculated torque Tc32 is obtained based on the correction torque ΔT32 corresponding to the delay time τ32 by the same method as the method of estimating the engine torque in the first embodiment. In addition, period T32 is an application period of calculated value torque Tc32.

In this case, it can be seen that since the engine torque change gradient is restricted by the method described above, the torque change gradient is slowed down as indicated by the predicted torque Te3. Therefore, it was found that the increase in the detected torque Td32 can be appropriately detected, and the detection torque Td32 can be appropriately corrected.

According to the engine torque estimation method of the third embodiment described above, the engine torque change gradient can be appropriately limited, and the accuracy of detecting a transient change in the engine torque can be improved.

Although the method of estimating the engine torque performed when the engine torque is increased has been described above, such an estimation method may be similarly performed when the engine torque is decreased. That is, it is possible to set a lower limit warning value for the filter time constant of the disturbance observer in the same procedure when the engine torque decreases, and prohibit commands requiring a gradient of the engine torque change such that the filter time constant is lower than the lower limit warning value. .

(fourth embodiment)

Next, a method of estimating engine torque according to the fourth embodiment will be described. Also in the fourth embodiment, basically the same method as the method of estimating the engine torque in the first embodiment is used. In the fourth embodiment, the difference from the first to third embodiments is that when shifting from the continuously variable transmission mode to the fixed transmission ratio mode, the correction of the detected torque is continued until the claw portion (refer to FIG. 2) Joining is complete. That is, in the fourth embodiment, even after the elements of the jaws are once synchronized, the ECU 4 continues to correct the detected torque in preparation for changes in the engine torque until the engagement of the jaws is completed. The reason for this is that, in the case of a structure in which the synchronous engagement of the jaws is performed after shifting, in the case where the detected torque is corrected by the above method, when the gradient of the engine torque fluctuates, it cannot be precisely corrected. If the behavior in the initial stage of torque change until the synchronization between the predicted torque and the detected torque is accurately estimated, the completion of the gear shift will be delayed, and a gear shift shock will occur.

Specifically, it will be described with reference to FIG. 14 . FIG. 14 is a diagram for explaining a problem that occurs when the correction of the detected torque is not continued until the engagement of the jaw portion is completed. In FIG. 14 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te41 shows an example of predicted torque, curve Td41 shows an example of detected torque, curve Tr41 shows an example of actual torque, and curves Tc411 and Tc412 show examples of calculated torque.

The calculated torque Tc411 is obtained based on the correction torque ΔT411 corresponding to the delay time τ411 by the same method as the method of estimating the engine torque in the first embodiment. This calculated value torque Tc411 is applied during the period T411. Specifically, the application of the calculated value torque Tc411 ends at time t412. At time t413 after this time t412, the synchronous condition of the jaws is satisfied, and the engagement operation of the jaws is performed, but the correction of the detected torque td41 is not performed for a period immediately after the time t413. At the subsequent time t414, a drop in the detected torque td41 is detected, whereby the detected torque td41 is corrected again. Specifically, calculated value torque Tc 412 is obtained based on correction torque Δ412 corresponding to delay time τ 412 . The calculated torque Tc412 is applied during the period T412.

In this case, torque variation occurs during the engaging operation after the synchronous condition of the jaw portion is satisfied, thereby causing a torque estimation error as indicated by the hatched area C1. Therefore, it is considered that a shift shock caused by a torque estimation error occurs. In addition, it is considered that a delay occurs in the completion of the shift.

Thus, in the fourth embodiment, the ECU 4 continues to correct the detected torque even after the jaw portion is once synchronized until the engagement is completed.

FIG. 15 is a diagram for explaining the effect of the engine torque estimation method of the fourth embodiment. In FIG. 15 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te42 shows an example of predicted torque, curve Td42 shows an example of detected torque, curve Tr42 shows an example of actual torque, and curve Tc42 shows an example of calculated torque.

The calculated torque Tc42 is obtained based on the correction torque Δ42 corresponding to the delay time τ42 by the same method as the method of estimating the engine torque in the first embodiment. Such a calculated value torque Tc42 is applied until the jaw engagement is completed. That is, even if the torque gradient is stabilized to some extent, the correction of the detected torque Td42 is continued until the engagement of the jaw portions is completed. Specifically, such calculated value torque Tc42 is applied during the period T42. Accordingly, it is possible to suppress the occurrence of a torque estimation error as shown by the hatched area C1 in FIG. 14 . Therefore, the jointability of the jaw portion can be improved, and a delay in shifting time, shifting shock, and the like can be suppressed.

16 is a flowchart showing engine torque estimation processing in the fourth embodiment. This process is repeatedly executed by the ECU 4 .

The processes of steps S201 to S206 and step S208 are the same as the processes of steps S101 to S106 and step S108 shown in FIG. 7 , respectively, and therefore description thereof will be omitted. Here, only the processing of step S207 will be described.

In step S207, the ECU 4 determines whether or not the engagement of the jaws is completed. Such determination is performed in order to continuously correct the detected torque until the engagement of the jaws is completed. When joining of the jaw parts is completed (YES in step S207), the process ends. In this case, the correction of the detected torque ends. On the other hand, when the joining of the jaw parts has not been completed ("No" in step S207), the process proceeds to step S208. In this case, the detected torque is continuously corrected.

According to the engine torque estimation method of the fourth embodiment described above, by continuing to correct the detected torque until the engagement of the jaws is completed, the engagement of the jaws can be improved, and delay in shifting time, shifting shock, and the like can be suppressed.

It is also possible to implement the fourth embodiment in combination with the above-mentioned second embodiment and/or third embodiment. That is, the detected torque can be continuously corrected until the engagement of the claw parts is completed, and at the same time, the second predetermined value and the filter time constant of the disturbance observer can be changed based on the change gradient of the predicted torque, and the filter time constant of the disturbance observer can be set The lower limit warning value prohibits commands that require a gradient of the engine torque change such that the filter time constant is lower than the lower limit warning value.

In addition, although the method of estimating the engine torque performed when the jaw portion is engaged has been described above, such an estimation method may be similarly performed when the jaw portion is disengaged. That is, it is possible to continue correcting the detected torque until separation of the jaw portion is completed.

(fifth embodiment)

Next, a method of estimating engine torque according to the fifth embodiment will be described. Also in the fifth embodiment, basically the same method as the method of estimating the engine torque in the first embodiment is used. However, the fifth embodiment is different from the first to fourth embodiments in that the delay time of the detected torque with respect to the predicted torque is learned, and the detection torque is corrected based on the delay time. Specifically, in the fifth embodiment, the ECU 4 learns the delay time of the detected torque with respect to the predicted torque that is synchronized as described above, and when the torque changes next time and onwards, the ECU 4 learns the delay time of the detected torque until a rise in the detected torque is detected. During the period, the detected torque is corrected based on the learned delay time. This is for accurately estimating the behavior at the initial stage of torque change until synchronization between the predicted torque and the detected torque is achieved.

FIG. 17 is a diagram for concretely explaining a method of estimating engine torque in the fifth embodiment. In FIG. 17 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te5 shows an example of predicted torque, curve Td5 shows an example of detected torque, curve Tr5 shows an example of actual torque, and curve Tc5 shows an example of calculated torque.

In the fifth embodiment, in order to appropriately correct the detected torque Td5 in the period indicated by the dotted line area E1 in FIG. 17 , the ECU 4 performs Correction of detection torque. Thus, the calculated value torque Tc5 is applied until a rise in the detected torque Td5 is detected.

For example, the ECU 4 stores this delay time in association with the values of the oil-water temperature, the intake air temperature, the engine speed, the torque, the filter value associated with the response of the disturbance observer, and the like. This is because the response characteristics of the engine torque are affected by the operating point (rotational speed, torque), torque change direction (rising side, falling side), oil-water temperature and/or intake air temperature at that moment.

18 is a flowchart showing engine torque estimation processing in the fifth embodiment. This process is repeatedly executed by the ECU 4 .

The processes of steps S301 to S303 and steps S305 to S309 are the same as the processes of steps S201 to S203 and steps S204 to S208 shown in FIG. 16 , respectively, and therefore description thereof will be omitted. Here, only the processing of step S304 and the processing of steps S310 to S312 will be described.

The process of step S304 is performed when the detected torque is greater than the second predetermined value (YES in step S303). In step S304, the ECU 4 stores the delay time of the learned detected torque with respect to the predicted torque (ie, the time difference between the predicted torque and the detected torque). Specifically, the ECU 4 stores the delay time in association with the values of the oil-water temperature, the intake air temperature, the engine speed, the torque, the filter value associated with the response of the disturbance observer, and the like related to the responsiveness of the engine torque. Next, the process proceeds to step S305.

On the other hand, the processing of steps S310 to S312 is performed when the detected torque is equal to or less than the second predetermined value ("No" in step S303). In step S310, ECU 4 stores the detected torque used in step S303. Then, the process proceeds to step S311.

In step S311 , the ECU 4 synchronizes the predicted torque and the detected torque with reference to the delay time (detection delay learning value) previously stored and learned in step S304 . Then, the process proceeds to step S312. It should be noted that, when there is no detection delay learning value due to incomplete learning, etc., the processing of step S311 may be performed using a predetermined initial value. Alternatively, when there is no detection delay learning value, the processing of S310 to S312 may not be performed.

In step S312, the ECU 4 calculates a correction torque for correcting the detected torque. Specifically, the ECU 4 calculates the amount of change in engine torque after the delay time based on the estimated torque that has been synchronized using the delay time from the actual engine torque change estimated by the first estimation method, and the engine torque The amount of torque change is used as the correction torque. Then, the process proceeds to step S312.

According to the engine torque estimation method of the fifth embodiment described above, the accuracy of detecting a transient change in engine torque can be further improved. Specifically, even when the torque direction changes as shown in FIG. 14 or when an intermittent change such as stepped acceleration and deceleration is requested, the engine torque can be estimated with high accuracy. .

Although the method of estimating the engine torque performed when the engine torque is increased has been described above, such an estimation method may be similarly performed when the engine torque is decreased. That is, when the engine torque decreases, the delay time of the detected torque with respect to the predicted torque can be learned by the same procedure, and the detected torque can be corrected based on the delay time.

In addition, the fifth embodiment may be implemented in combination with the above-mentioned second embodiment and/or third embodiment. That is, the detected torque can be corrected based on the learned delay time, and at the same time, the second predetermined value and the filter time constant of the disturbance observer can be changed based on the change gradient of the predicted torque. A lower limit warning value is set, and a command that requires a filter time constant lower than the lower limit warning value for an engine torque change gradient is prohibited.

Furthermore, although the example of combining the fifth embodiment and the above-mentioned fourth embodiment was shown above (see FIG. 18 ), it may be implemented without combining the fifth embodiment and the fourth embodiment. That is, the detection torque may not be continuously corrected until the engagement of the jaw portion is completed. However, when there is a large difference in responsiveness of the engine torque between the rising side and the falling side of the torque, it can be said that it is preferable to implement the combination of the fifth embodiment and the fourth embodiment.

(sixth embodiment)

Next, the method of estimating the engine torque according to the sixth embodiment will be described. Also in the sixth embodiment, basically the same method as the method of estimating the engine torque in the first embodiment is used. However, the sixth embodiment differs from the first to fifth embodiments in that the predicted torque obtained by the second estimation method is corrected based on changes in state values associated with changes in engine torque. Specifically, in the sixth embodiment, the ECU 4 corrects the predicted torque in consideration of the influence of the change in the engine speed accompanying the gear shift, and corrects the detected torque using the corrected predicted torque. This is because the predicted torque used in the above-mentioned method of estimating the engine torque is the value of the engine speed before the shift, so when the shift is performed after the prediction, there may be a deviation between the predicted torque and the actual torque. , There is also a tendency to deviate between the obtained calculated value torque and the actual torque.

FIG. 19 is a diagram for explaining problems that occur when predicted torque deviates from actual torque (and detected torque). In FIG. 19 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te61 shows an example of predicted torque, curve Td61 shows an example of detected torque, curve Tr61 shows an example of actual torque, and curve Tc61 shows an example of calculated torque. The calculated torque Tc61 is obtained based on the correction torque ΔT61 corresponding to the delay time τ61 by the same method as the method of estimating the engine torque in the first embodiment. In addition, the period T61 is an application period of the calculated value torque Tc61.

In this case, since the engine speed changes as indicated by the arrows in FIG. 19 , a deviation occurs between the predicted torque Te61 and the actual torque Tr61 (and the detected torque Td61 ). Specifically, as shown in FIG. 19 , it is found that the gradient of the predicted torque Te61, the gradient of the actual torque Tr61, and the detected torque Td61 are different. Therefore, it can be seen that the calculated torque Tc61 obtained based on the predicted torque Te61 deviates from the actual torque Tr61 as indicated by the dotted line area F1 in FIG. 19 .

However, in the sixth embodiment, the ECU 4 corrects the predicted torque in consideration of the influence of the change in the engine speed accompanying the gear shift, and corrects the detected torque using the corrected predicted torque. Specifically, the ECU 4 applies a correction that takes into account the influence of the actual measurement value or the predicted value of the engine rotation speed accompanying the gear shift.

FIG. 20 is a diagram for concretely explaining a method of estimating engine torque according to the sixth embodiment. In FIG. 20 , time is shown on the horizontal axis, and engine torque is shown on the vertical axis. Specifically, curve Te62 shows an example of predicted torque, curve Te63 shows an example of corrected predicted torque, curve Td62 shows an example of detected torque, curve Tr62 shows an example of actual torque, and curve Tc62 shows An example of calculated value torque.

In the sixth embodiment, the ECU 4 corrects the deviation of the predicted torque Te62 accompanying the change of the engine rotational speed as indicated by the arrow in FIG. 20 . Thereby, predicted torque Te63 shown by the two-dot chain line in FIG. 20 is obtained. Hereinafter, the predicted torque corrected in this way is referred to as "rotation corrected predicted torque". Thereafter, the ECU 4 obtains a correction torque ΔT62 corresponding to the delay time τ62 using the rotation correction predicted torque Te63. Then, the ECU 4 adds a correction torque ΔT62 to the detected torque Td62 to calculate a calculated value torque Tc62. This calculated torque Tc62 is found to substantially coincide with the actual torque Tr62 as indicated by the dotted line region F2 in FIG. 20 . Period T62 is an application period of calculated value torque Tc62.

21 is a flowchart showing engine torque estimation processing in the sixth embodiment. This process is repeatedly executed by the ECU 4 .

The processing in steps S401 to S406 and steps S409 to S412 is the same as the processing in steps S301 to S306 and steps S308 to S311 shown in FIG. 18 , respectively, and therefore description thereof will be omitted. In addition, since the processing of steps S413-S414 is the same as the processing of steps S407-S408, description is abbreviate|omitted. Here, only the processing of steps S407 to S408 will be described.

The processing of steps S407 to S408 is performed after the synchronization between the predicted torque and the detected torque is acquired. In step S407 , the ECU 4 calculates a predicted torque corrected using the current engine speed information (rotation correction predicted torque) for the synchronized predicted torque. For example, the ECU 4 calculates the rotation correction predicted torque using the relationship between the engine intake air charge amount and the engine speed, and the like. Then, the process proceeds to step S408.

In step S408, the ECU 4 calculates a correction torque for correcting the detected torque. Specifically, the ECU 4 calculates the engine torque change amount after the delay time based on the rotation correction predicted torque obtained in step S408 using the delay time estimated by the first estimation method with respect to the actual engine torque change, This amount of change in engine torque is used as correction torque. Then, the process proceeds to step S409.

According to the method of estimating the engine torque of the sixth embodiment described above, the accuracy of detecting a transient change in the engine torque can be further improved. Specifically, it is possible to effectively improve the estimation accuracy of the engine torque in the second half of the shift.

Although the method of estimating the engine torque performed when the engine torque is increased has been described above, such an estimation method may be similarly performed when the engine torque is decreased. That is, when the engine torque decreases, the predicted torque can be corrected based on the change in the engine rotational speed by the same procedure, and the detected torque can be corrected using the corrected predicted torque.

In addition, the sixth embodiment may be implemented in combination with the above-mentioned second embodiment and/or third embodiment. That is, the corrected predicted torque can be used to correct the detected torque, and at the same time, the second predetermined value and the filter time constant of the disturbance observer can be changed based on the change gradient of the predicted torque, and the filter time of the disturbance observer The constant sets the lower limit warning value, and prohibits commands that require a filter time constant lower than the lower limit warning value for an engine torque change gradient.

In addition, although the example in which the sixth embodiment is combined with the above-mentioned fourth embodiment has been described above (see FIG. 21 ), it may be implemented without combining the sixth embodiment and the fourth embodiment. That is, the correction of the detected torque may not be continued until the engagement of the jaw portion is completed.

Furthermore, although the example in which the sixth embodiment is combined with the above-mentioned fifth embodiment has been described above (see FIG. 21 ), it may be implemented without combining the sixth embodiment and the fifth embodiment. That is, the correction of the detected torque may not be performed based on the learned delay time.

Furthermore, although the above shows an example of correcting the predicted torque based on the change in the engine speed, as long as it is a state value related to a change in the engine torque other than the engine speed, the predicted torque can also be corrected using such a value. .

[modified example]

In the above, although an example is shown in which the detected torque estimated by the first estimation method is corrected by using the predicted torque estimated by the second estimation method, the torque estimated by the first estimation method may be used instead. The detected torque corrects the predicted torque estimated by the second estimation method.

In the above, the method of estimating the engine torque based on the rotation speed change information of the first motor generator MG1 was shown as the first estimation method. In another example, the engine torque may be estimated using a rotational speed detection means such as a resolver instead of a motor generator.

In the above, the method of estimating the engine torque based on the intake air amount of the engine has been described as the second estimation method. In another example, when the engine is a diesel engine, the engine torque may be estimated based on the fuel injection amount and/or the state quantity of the turbocharger, and the like.

The present invention is not limited to the structure in which the motor generator is connected to either the engaging element or the engaged element, and may be applied to the structure in which the motor generator is connected to both the engaging element and the engaged element.

The present invention is not limited to the application to the meshing mechanism (dog stopper 7) for switching the transmission mode between the continuously variable transmission mode and the fixed transmission ratio mode, but can also be applied to a structure capable of fixing the first motor generator MG1 The mechanism of the rotor 11 (the so-called MG1 locking mechanism). Furthermore, the present invention is not limited to application to meshing mechanisms, and may be applied to mechanisms such as wet multi-plate clutches and cam clutches.

The present invention is not limited to application when switching the transmission mode between the continuously variable transmission mode and the fixed transmission ratio mode. In addition, the invention can also be applied when the engine torque changes.

The invention is not limited to application to hybrid vehicles. Further, the present invention is not limited to application in the case of estimating engine torque. The present invention can also be applied to the case of estimating changes in objects on the time axis other than engine torque. That is, the present invention can use the method of estimating the change of the object with a delay relative to the change of the actual object, and the method of estimating the change of the object before the change of the object actually occurs, so that changes other than the engine torque can be performed. presumption.

Industrial Utilization Possibility

The present invention can be used for hybrid vehicles and the like.

Claims (53)

1. A device for estimating engine torque, which estimates engine torque, is characterized in that it has: a first estimating unit that estimates the engine torque with a delay relative to an actual change in the engine torque; a second estimating unit that estimates the engine torque before the engine torque actually changes; and A correcting unit that, when the engine torque changes, corrects the first estimating unit based on the second estimating unit to obtain the engine torque. 2. The engine torque estimating device according to claim 1, wherein: said correction unit, calculating an amount of change in the engine torque within a delay time of the estimation by the first estimating means with respect to an actual change in the engine torque, using the second estimating means, The correction is performed by adding or subtracting the calculated change amount to the engine torque estimated by the first estimating means. 3. The engine torque estimating device according to claim 1, wherein: The correcting means performs the correction when the change in the engine torque estimated by the first estimating means is greater than a predetermined value. 4. The engine torque estimating device according to claim 2, wherein: The correcting means performs the correction when the change in the engine torque estimated by the first estimating means is greater than a predetermined value. 5. The engine torque estimating device according to claim 3, wherein: The correcting means changes the predetermined value based on the gradient of the change in the engine torque estimated by the second estimating means. 6. The engine torque estimating device according to claim 4, wherein: The correcting means changes the predetermined value based on the gradient of the change in the engine torque estimated by the second estimating means. 7. The engine torque estimating device according to claim 1, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 8. The engine torque estimating device according to claim 2, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 9. The engine torque estimating device according to claim 3, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 10. The engine torque estimating device according to claim 4, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 11. The engine torque estimating device according to claim 5, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 12. The engine torque estimating device according to claim 6, wherein: The first estimating unit changes a ratio of the engine torque estimated by the first estimating unit to the actual engine torque based on the gradient of the change in the engine torque estimated by the second estimating unit. Adjust the control value of the delay time of the moment change, so that the delay time changes. 13. The engine torque estimating device according to claim 7, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 14. The engine torque estimating device according to claim 8, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 15. The engine torque estimating device according to claim 9, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 16. The engine torque estimating device according to claim 10, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 17. The engine torque estimating device according to claim 11, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 18. The engine torque estimating device according to claim 12, wherein: The first estimating unit, when changing a control value for adjusting the delay time, sets a lower limit warning value used for the control value, The engine torque estimating device further includes a control unit that performs control to limit a change in the engine torque so that the control value complies with the lower limit warning value. 19. The engine torque estimating device according to any one of claims 1 to 18, wherein: The correction unit learns a delay time of the estimation performed by the first estimation unit relative to the estimation performed by the second estimation unit, and performs the correction based on the learned delay time. 20. The engine torque estimating device according to claim 19, wherein: The correcting means performs the correction based on the learned delay time when the change in the engine torque estimated by the first estimating means is equal to or less than a predetermined value. 21. The engine torque estimating device according to any one of claims 1 to 18, wherein: The correcting unit corrects the engine torque estimated by the second estimating unit based on a change in a state value associated with a change in the engine torque, and performs a correction based on the corrected engine torque. A correction of the first estimation unit. 22. The engine torque estimating device according to claim 19, wherein: The correcting unit corrects the engine torque estimated by the second estimating unit based on a change in a state value associated with a change in the engine torque, and performs a correction based on the corrected engine torque. A correction of the first estimation unit. 23. The engine torque estimating device according to claim 20, wherein: The correcting unit corrects the engine torque estimated by the second estimating unit based on a change in a state value associated with a change in the engine torque, and performs a correction based on the corrected engine torque. A correction of the first estimation unit. 24. The engine torque estimating device according to any one of claims 1 to 18, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 25. The engine torque estimating device according to claim 19, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 26. The engine torque estimating device according to claim 20, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 27. The engine torque estimating device according to claim 21, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 28. The engine torque estimating device according to claim 22, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 29. The engine torque estimating device according to claim 23, wherein: the first estimation unit estimates the engine torque based on a disturbance observer, The second estimating unit estimates the engine torque based on an intake air amount of the engine. 30. The engine torque estimating device according to any one of claims 1 to 18, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 31. The engine torque estimating device according to claim 19, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 32. The engine torque estimating device according to claim 20, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 33. The engine torque estimating device according to claim 21, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 34. The engine torque estimating device according to claim 22, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 35. The engine torque estimating device according to claim 23, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 36. The engine torque estimating device according to claim 24, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 37. The engine torque estimating device according to claim 25, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 38. The engine torque estimating device according to claim 26, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 39. The engine torque estimating device according to claim 27, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 40. The engine torque estimating device according to claim 28, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 41. The engine torque estimating device according to claim 29, wherein: The engine torque estimating device is suitable for use in a hybrid vehicle in which a speed change mode is switched between a continuously variable speed change mode and a fixed speed change ratio mode by switching engagement and disengagement of engaging elements with each other, The correction means performs the correction when the shift mode is switched. 42. The engine torque estimating device according to claim 30, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 43. The engine torque estimating device according to claim 31, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 44. The engine torque estimating device according to claim 32, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 45. The engine torque estimating device according to claim 33, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 46. The engine torque estimating device according to claim 34, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 47. The engine torque estimating device according to claim 35, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 48. The engine torque estimating device according to claim 36, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 49. The engine torque estimating device according to claim 37, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 50. The engine torque estimating device according to claim 38, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 51. The engine torque estimating device according to claim 39, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 52. The engine torque estimating device according to claim 40, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed. 53. The engine torque estimating device according to claim 41, wherein: The correction unit continues to perform the correction until the bonding of the bonding elements is completed.